1. Field of the Invention
The invention relates to trocar assemblies. More particularly, the invention relates to a trocar sealing assembly including a protector minimizing detrimental contact between inserted instruments and the seal body.
2. Description of the Prior Art
A trocar assembly is a surgical instrument that is used to gain access to a body cavity. A trocar assembly generally comprises two major components, a trocar sleeve, composed of a trocar housing and a trocar cannula, and a trocar obturator. The trocar cannula, having the trocar obturator inserted therethrough, is directed through the skin to access a body cavity. Once the body cavity is accessed, laparoscopic or arthroscopic surgery and endoscopic procedures may be performed. In order to penetrate the skin, the distal end of the trocar cannula is placed against the skin that has been previously cut with a scalpel. The trocar obturator is then used to penetrate the skin and access the body cavity. By applying pressure against the proximal end of the trocar obturator, the sharp point of the trocar obturator is forced through the skin until it enters the body cavity. The trocar cannula is inserted through the perforation made by the obturator and the obturator is withdrawn, leaving the trocar cannula as an access way to the body cavity.
The proximal end portion of the trocar cannula is typically joined to a trocar housing that defines a chamber having an open distal end portion in communication with the interior lumen defined by the trocar cannula. A trocar obturator, or other elongated surgical instruments or tools, axially extend into and are withdrawn from the trocar cannula through the proximal end portion of the chamber defined by the trocar housing.
It is common for a sealing arrangement or sealing device to be used in association with the trocar cannula and trocar housing to prevent the escape of fluid or gas during endoscopic procedures. During an endoscopic surgical procedure, the internal gas pressure must be maintained in order to successfully complete the procedure. In order to maintain the internal gas pressure while instruments are passed into and out of the trocar sleeves positioned in the abdominal cavity, sealing devices are required for both the trocar obturator and instruments passing through he trocar cannula.
Seals must also offer good tear resistance, resistance to snagging and low friction with respect to the insertion or removal of surgical instruments. Angular insertion of instruments relative to the central axis of the trocar cannula and instrument tip sharpness are driving factors in trocar seal failures. These two factors can cause “tenting” of the seal material. Once tenting occurs, continued distal motion of the penetrating instrument will result in seal tearing.
As such, a need exists for a protector capable of protecting the seal as an obturator or instrument is passed through the trocar cannula. In particular, a need exist for a protector which may be used in conjunction with duckbill seals commonly utilized in trocar assemblies. The present invention provides such a protector.